The first internally installed mass damper for mountain bikes made of 97% pure tungsten The TMD reduces vibrations and fatigue in a compact design Aluminum and steel, tapered and 1 1/8" steerers, single and dual crown, oval or cylindrical are all compatible(steerer length of 190mm+ required) IGUS bushings allow the mass to move freely between the 2 springs and are self lubricating Three die spring options are included and calibrated to carefully chosen frequencies(blue-light, yellow-medium and red-heavy) 420g TECH SPECS table{border-collapse:collapse;width:100%;} td{text-align:left;padding:8px;font-weight:350;} tr:nth-child(even){background-color:#f2f2f2} th{background-color:#eb212e;color:white;text-align:left;padding:8px;} .desc .specs-heading{font-size:24px;font-weight:600;padding-top:35px;border-top:3px solid #f0f0f0;display:inline-block;border-bottom:4px solid #eb212e;width:142px;margin:0;} Model V2 Tuned Mass Damper Description Headtube installed to reduce vibrations and fatigue